Privacy Preserving Multi-Proxy Based Encrypted Keyword Search

Abstract

This paper presents a multi-proxy (2 proxies) based encrypted keyword search scheme that enjoys the following properties: This scheme provides data confidentially that encrypted data does not leak any keywords and documents to the attackers (data server and a proxy). Moreover, the proposed scheme provides trapdoor privacy. In other words, the attackers do not learn any information about searched keywords. Furthermore, even if a proxy is controlled by an attacker, the attacker does not learn any information about the queries (keywords that the user searches over the database) and database results. Different from other studies, this scheme provides lightweight user-side query and data processing. In other words, most of the job (query processing) is done by the proxies on behalf of the user. Finally, the proposed scheme relaxes the trust assumption that eliminates a single point of failure by introducing multi-proxy architecture.